JPH0753914A - Coated automotive member - Google Patents

Abstract

PURPOSE:To obtain a polypropylene resin compsn. for molding which has well- balanced mechanical strengths and high moldability and molded appearance. CONSTITUTION:An automotive member is produced by directly coating a molded item which has a ratio of the concn. of O atoms that of C atoms on the surface of 0.5% or greater and a bending modulus of 7,000kg/cm<2> or greater and is produced from a resin compsn. comprising 40-80wt.% propylene-ethylene block copolymer, 10-50wt.% ethylene-styrene elastomer, 1-15wt.% ethylene-propylene copolymer rubber having a Mooney viscosity ML1+4 at 100 deg.C of 5 or lower, 0.01-10wt.% hydroxylated diene polymer or its hydrogenation product, 3-40wt.% at least either talc having a particle diameter of 5mum or lower or at least one filler selected from the group consisting of AlBO3, K2TiO3, MgSO4, and CaCO3 all having particle sizes of 2mum or lower and an average aspect ratio of 5 or greater, and if necessary 0-25wt.% ethylene-unsatd. carboxylic acid copolymer and 0-10wt.% phosphorus oxy-acid compd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle member having a coating directly applied to the surface of a molded article for automobile parts.

[0002]

Conventionally, exterior members such as fenders, door panels, bumpers, spoilers, mat guards, side moldings, wheel caps and instrument panels,
In many cases, automotive parts made of propylene-based resin used as levers, knobs, linings, etc. are put to practical use after being wholly or partially painted. However, since an automobile member made of a propylene resin does not have a polar group in the structure of the material itself, it is difficult to obtain a practical level of paint adhesion strength when the paint is directly applied. Therefore, in many cases, the surface of the automobile member which has been molded in advance is subjected to TCE (trichloroethane) degreasing treatment, a primer is applied, a plasma treatment is applied, and the like to improve the paint adhesion performance.

[0003]

However, such a coating method has hitherto had the following problems. First of all, the TCE degreasing process is banned from 1995 onwards by the Montreal Protocol. In addition, the primer coating method has the drawback that the coating cost is high because an expensive primer must be used and the coating constant is large, but in addition to that, it is necessary to volatilize the solvent of the primer. However, there was a risk of fire and there was a problem with safety. On the other hand, in the plasma processing method, since a high degree of vacuum is required, an expensive device must be installed, and the cost increase cannot be avoided because of the batch method. In addition, it is difficult to apply uniform treatment to recent automobile parts with complicated shapes, and the adhesion of paint decreases when it comes into contact with foreign matter, which may cause variations in coating film performance. It was inconvenient for me. Therefore, if the steps of TCE treatment, primer coating, and plasma treatment in the coating of automobile parts made of propylene resin can be omitted, the coating process can be simplified, the working environment can be improved, and the cost can be reduced. Therefore, many studies have been conducted so far so as to omit these steps. However, in many cases, the propylene-based resin automobile members are coated without being indispensable for such TCE treatment, primer coating and plasma treatment. In addition, when such a treatment is not performed, the coating film strength is insufficient or the elastic modulus of the material is low, and the application is often limited.

[0004]

[Means for Solving the Problems]

[Summary of the Invention] The inventors of the present invention have conducted various studies in order to achieve the above-mentioned object, and as a result, an automobile member molded using a specific propylene-based resin composition was directly coated with a paint. Nevertheless, they have found that they have practically sufficient paint adhesion performance and mechanical strength, and have completed the present invention.

That is, the coated automotive member of the present invention has the following components (a), (b), (c), (d) and (e):
Depending on the case, a molded product obtained by X-ray photoelectron spectroscopy (XPS / ESCA) using a resin composition consisting of each of the components (f) or (g) or both as essential components. When the concentration of oxygen atoms relative to the carbon atoms on the surface is 0.5% or more, the flexural modulus is 7,000 kg /
It is characterized in that a coating film is directly formed on the surface of a molded article for automobile parts which satisfies the condition of being not less than cm ² . Component (a): Contains 4 to 30% by weight of room temperature xylene-soluble matter having an ethylene content of 20 to 70% by weight, the MFR of the whole copolymer is 1 to 200 g / 10 minutes, and the ethylene content is Propylene / ethylene block copolymer of 3 to 21% by weight 40 to 80% by weight Component (b): At least one elastomer selected from ethylene elastomer and styrene elastomer 10 to 50% by weight Component (c) : Mooney viscosity ML _{1 + 4} (100 ° C.) is 5 or less, MFR (230 ° C., 2.16 kg) is 30 g / 10 min or more, and propylene content is 20 to 35% by weight of ethylene / propylene copolymer rubber 1 to 15 Weight% Component (d): Diene polymer having a hydroxyl group at the end or hydrogenated product thereof 0.01 to 10% by weight Component (e): Talc having an average particle size of 5 μm or less, or an average particle size of 2 μm or less Aluminum borate whiskers having an average aspect ratio of 5 or more, potassium titanate whiskers, magnesium sulfate whiskers (magnesium oxysulfate whiskers: MgSO4 · 5Mg (OH) 2 · 3H2O), titanium oxide whiskers and calcium carbonate whiskers. At least one filler selected from whiskers 3 to 40% by weight Component (f): Ethylene / unsaturated carboxylic acid copolymer 0 to 25% by weight Component (g): Phosphorus oxyacid compound 0 to 10% by weight

[Detailed Description of the Invention] [I] Production of Polymer Composition (1) Raw Material (a) Constituent Components (Essential Components) Component (a): Propylene / Ethylene Block Copolymer The coating of the present invention was applied. The propylene / ethylene block copolymer as the component (a) in the resin composition used in the member for automobiles has a content of ethylene of 20 to 70% by weight and a substantially amorphous room temperature xylene soluble component of 4 to 4. Resin containing 30% by weight, preferably 6 to 25% by weight, and MFR (230 ° C., 2.16) of the whole copolymer resin.
kg) is 1 to 200 g / 10 minutes, preferably 10 to 10
0 g / 10 minutes and the total ethylene content is 3 to 2
1% by weight, preferably 3-18% by weight. Here, the ethylene content is a value measured by an infrared spectrum analysis method or the like, and the room temperature xylene-soluble component is dissolved by immersing 2 g of a sample in 500 g of boiling xylene for 20 minutes and then cooling to room temperature. The solid phase is a value calculated by back-calculating the solid phase weight obtained by filtering the precipitated solid phase with a glass filter, and the MFR is measured according to JIS-K7210.

When the ethylene content and the room temperature xylene-soluble content of the copolymer resin are less than the above ranges, the impact resistance is poor when the coated automotive parts of the present invention are used. If it exceeds the above range, the rigidity is insufficient. A usual stereoregular catalyst is used for the production of this copolymer resin. This propylene / ethylene block copolymer is a copolymer of other unsaturated monomers (for example, butene-1,
Terpolymers or more containing α-olefins such as hexene-1, vinyl esters such as vinyl acetate, unsaturated organic acids such as (meth) acrylic acid (ester) and maleic anhydride, or derivatives thereof} It may be any of graft type, random type and block type). Here, the compounding amount of the propylene / ethylene block copolymer as the component (a) is 40 to 80% by weight, preferably 50 to 70% by weight. When the compounding amount of the component (a) is less than the above range, the moldability is poor, and when it exceeds the above range, the physical property balance and the coating performance are deteriorated, which is not suitable.

Component (b): Elastomer The elastomer of component (b) in the resin composition used in the coated automotive parts of the present invention is ethylene.
Ethylene elastomers such as propylene binary copolymer rubber (EPM), ethylene / propylene / non-conjugated diene ternary copolymer rubber (EPDM), ethylene / propylene / butene-1 ternary copolymer rubber, hydrogenated styrene / butadiene / It is at least one selected from styrene elastomers such as styrene block copolymers and hydrogenated styrene / isoprene block copolymers. ethylene·
The propylene binary copolymer rubber (EPM) has a propylene content of 20 to 55% by weight, preferably 20 to 50% by weight, and a Mooney viscosity ML _{1 + 4} (100 ° C.) of 15 to 100, particularly preferably 15 to 90. Is. In addition, ethylene
Propylene / non-conjugated diene terpolymer rubber (EPDM)
Then, those having an iodine value of 20 or less are preferable. ethylene·
In the propylene / butene-1 terpolymer rubber, the content of propylene and butene-1 is respectively 20 to 55% by weight, preferably 25 to 50% by weight, and 3 to 15% by weight, preferably 5 to 12% by weight. % By weight. here,
The content of each component is a value measured by an infrared spectrum analysis method, an ordinary NMR method, or the like. Further, for example, a hydrogenated styrene / butadiene / styrene block copolymer and a hydrogenated styrene / isoprene block copolymer are a fully or partially hydrogenated styrene / butadiene / styrene block copolymer and a styrene / isoprene block copolymer, respectively. Combined, so-called styrene / ethylene / butylene / styrene block copolymer of styrene / isoprene / styrene block copolymer, styrene / ethylene /
Propylene block copolymers, styrene / ethylene / propylene / styrene block copolymers, etc.
The hydrogenation rate is 95% or more, preferably 99% or more. The styrene content is preferably 5 to 50% by weight, particularly preferably 10 to 50% by weight.

Any of these elastomers out of the above range is not suitable because of poor coating performance and physical property balance. Also,
The elastomer is preferably amorphous in nature,
A crystallinity of 5% or less is preferable. The manufacturing method and shape of these are not particularly limited. Here, the blending amount of the component (b) is 10 to 50% by weight, preferably 20 to 40% by weight, and particularly 20 to 35% by weight from the viewpoint of coating performance. If it is less than the above range, the coating strength and impact resistance are poor, and
If it exceeds the above range, the heat resistance and the surface hardness are deteriorated, which is not suitable.

Component (c): Ultra-low viscosity ethylene / propylene binary copolymer rubber Component (c) ultra-low-viscosity ethylene / propylene binary resin in the resin composition used in the coated automotive parts of the present invention Copolymer rubber has Mooney viscosity ML _{1 + 4} (100
℃) is 5 or less, MFR (230 ℃, 2.16kg) is 3
The propylene content is 0 g / 10 minutes or more, preferably 40 g / 10 minutes or more, and the propylene content is 20 to 35% by weight. MFR (230 ℃, 2.16kg) is 30g / 10
If it is less than the amount, it is not suitable because the effect of improving the coating performance is lost, and if the addition amount exceeds 10% by weight, there is no problem in the coating performance, but it is not suitable because it deteriorates the physical property balance. . The compounding amount of the component (c) is 1 to 1
It is 5% by weight, preferably 2-10% by weight.

Component (d): a diene polymer having a hydroxyl group at the terminal or a hydrogenated product thereof A diene polymer having a hydroxyl group at the terminal of the component (d) in the resin composition used in the automotive member coated with the present invention. Alternatively, the hydrogenated product thereof is, for example, polyhydroxypolybutadiene. Specifically, it has at least one hydroxyl group at the terminal and has a molecular weight of 200 to 100,0.
00, preferably 500-50,000, particularly preferably 800-10,000, liquid, semi-solid, solid polymers at ambient temperature are included. The average number of hydroxyl groups per molecule is generally 1.0 to 10.0, preferably 1.5 to 5.0, and the hydroxyl value is generally 15 to 250, preferably 25 to 125 (KOHmg / g). Is preferred.

The diene polymer having a hydroxyl group at the terminal is
A known method using 1,3-diene as a raw material, for example,
It can be produced by a radical polymerization method, an anionic polymerization method, or the like. Specifically, for example, Japanese Patent Laid-Open No. 51-7139.
The method described in Japanese Patent No. 1 can be mentioned. In the case of producing by the above radical polymerization method, it can be easily obtained by polymerizing a diene monomer using hydrogen peroxide as a polymerization initiator. Further, in the case of producing by the above-mentioned anionic polymerization method, at least one of both terminals obtained by polymerizing a conjugated diene according to a well-known method using an anionic polymerization catalyst, for example, an alkali metal or an organic alkali metal compound. Living polymer having a structure in which an alkali metal is bonded to, for example, monoepoxy compound, formaldehyde, acetaldehyde, acetone,
Alternatively, halogeno alkylene oxide and polyepoxy di may be reacted. At least one conjugated diene monomer is used as a raw material monomer for these polymers. Examples of the conjugated diene monomer include 1,3-butadiene, 1,3-pentadiene, isoprene, chloroprene, 2,3-dimethyl-1,3-butadiene, 1-phenyl-1,3-butadiene and the like.

As the hydrogenated product of the diene polymer having a hydroxyl group at the terminal, the above-mentioned diene polymer having a hydroxyl group at the terminal can be prepared by a conventional method, for example, JP-A-51-71.
It is obtained by hydrogenation by the method described in Japanese Patent No. 391 or the like. Regarding the degree of hydrogenation, the double bond contained in the polymer may be wholly or partially hydrogenated, but the iodine value is usually 0-2.
0.0, especially 0-5.0 (g / 100g) is preferable. These diene polymers having a hydroxyl group at the terminal and hydrogenated products thereof can be used alone or as a mixture of a plurality of them.

The blending amount of the component (d) is 0.01-10.
%, Preferably 0.1 to 7% by weight, particularly preferably 0.5 to 5% by weight. If the blending amount of component (d) is less than the above range, the reproducibility of paint adhesion may be poor, or the coating strength may be weak. Further, if the compounding amount of the component (d) exceeds the above range, not only is it uneconomical, but bleeding out of the polymer occurs, so that the coating strength is rather lowered.
Further, the strength as an automobile member cannot be maintained.

Component (e): Filler The filler of component (e) in the resin composition used in the coated automotive parts of the present invention has an average particle size of 5 μm.
m or less, and particularly preferably a specific surface area of 37,000 cm
² / g or more, substantially the entire length of 15μm or less was an average particle size of 0.8~2.2μm and an average aspect ratio of 5 or more of talc, average particle size is 2μm or less and an average aspect ratio Aluminum borate whiskers with a value of 5 or more, potassium titanate whiskers, magnesium sulfate whiskers (magnesium oxysulfate whiskers:
At least one filler selected from MgSO4 .5Mg (OH) 2 .3H2 O), titanium oxide whiskers and calcium carbonate whiskers can be used.

The talc used in the present invention is, for example, crushed talc raw stone by an impact type crusher or a micron mill type crusher, further finely crushed by a micron mill or jet type crusher, and then classified by a cyclone or a micron separator. It was manufactured by Here, the talc ore is preferably produced in China because it contains less metal impurities. Furthermore, the specific surface area is 37,
Less than 000 cm ² / g, average aspect ratio less than 5,
If talc having an average particle size of more than 5 μm is used, the impact strength and the coating appearance of the automobile member injection-molded with the resin composition of the present invention are poor, which is not preferable. For whiskers, those having an average particle size of more than 2 μm are unsuitable because the coating appearance of automobile parts and the dimensional stability at high temperatures are poor. Above all, the combined use of talc and each of the above whiskers is more preferable. Here, the average particle diameter is measured by a liquid phase sedimentation light transmission method, and the measuring device is, for example, Shimadzu SA-
There is a CP type, and the specific surface area is measured by the air permeation method. An example of the measuring device is SS-100 type manufactured by Shimadzu Corporation, and the aspect ratio is measured by a microscope method or the like. These fillers may be surface-treated with a surfactant, a coupling agent or the like, which is effective for improving the strength and paintability of automobile members. Here, the compounding amount of the filler of the component (e) is 3 to 40% by weight, preferably 3 to 35% by weight, and particularly preferably 3 to 30% by weight. If the content of the filler of component (e) is less than the above range, the rigidity and dimensional stability of the automobile member will be poor, and if it exceeds the above range, the coating appearance and impact strength of the automobile member will be remarkably inferior and unsuitable.

(B) Additional components The resin composition used in the coated automotive member of the present invention basically comprises the above-mentioned components (essential components), but In order to improve coatability, the following additional components (components (f) and (g)) can be blended in addition to the above-mentioned essential components (a) to (e). .

Component (f): Ethylene / unsaturated carboxylic acid copolymer The component (e) of the ethylene / unsaturated carboxylic acid copolymer in the resin composition used in the coated automotive parts of the present invention is , A copolymer of ethylene and an unsaturated carboxylic acid. The unsaturated carboxylic acid has 3 to 10 carbon atoms.
8, preferably 3 to 5 unsaturated carboxylic acids, specifically acrylic acid, methacrylic acid, itaconic acid, maleic anhydride, maleic acid monomethyl ester, maleic acid monoethyl ester and the like are used. Among these unsaturated carboxylic acids, acrylic acid and methacrylic acid are particularly preferably used. The ethylene / unsaturated carboxylic acid copolymer used in the present invention may contain a third component in addition to ethylene and the unsaturated carboxylic acid as described above. As such a third component, Unsaturated carboxylic acid esters such as ethyl acrylate, isobutyl acrylate, normal butyl acrylate, and methyl methacrylate, and carboxylic acid esters having 4 to 9 carbon atoms such as vinyl esters such as vinyl acetate are used. The ethylene / unsaturated carboxylic acid copolymer has an ethylene content of 50 to 99% by weight,
Preferably 70 to 98% by weight and unsaturated carboxylic acids are present in an amount of 50 to 1% by weight, preferably 30 to 2% by weight. When the ethylene / unsaturated carboxylic acid copolymer contains a third component in addition to the ethylene component and the unsaturated carboxylic acid component, the third component is 0 to 4
It is desirable to be present in an amount of 0% by weight, preferably 0-30% by weight. The amount of the component (e) compounded is 0 to 25% by weight, preferably 0.5 to 10% by weight.

Component (g): phosphorus oxyacid compound The phosphorus oxyacid compound of component (g) in the resin composition used in the coated automotive parts of the present invention has an oxygen atom directly bonded to a phosphorus atom. Structure (phosphorus oxyacid structure)
Of these, compounds having a phosphoric acid ester structure are preferable, and acidic phosphoric acid ester derivatives are particularly preferable. Specific examples include phosphoric acid monobutyl ester, phosphoric acid dibutyl ester, phosphoric acid di (2-ethylhexyl) ester, phosphoric acid mono (isodecyl) ester, phosphoric acid di (isodecyl) ester, phosphoric acid mono (lauryl) ester and the like. Here, the compounding amount of the phosphorus oxyacid compound as the component (g) is 0 to 10
% By weight, preferably 0.1 to 7, particularly preferably 0.5
~ 5% by weight. If it exceeds 10% by weight, the physical property balance is deteriorated, which is not suitable.

(C) Optional Ingredients In the resin composition of the present invention, a pigment for coloring is usually added, or in order to improve other various properties,
In addition to the above essential components (a) to (e) and additional components (components (f) and (g)), optional components may be added. As the optional component, various additives such as an antioxidant, an antistatic agent, a flame retardant and a dispersant can be added. Further, various resins other than the components (a) to (g), various elastomers, glass fibers, glass balloons, and various fillers such as carbon fibers may be blended within a range that does not significantly impair the effects of the present invention. it can. Among them, the linear ethylene copolymer described below is particularly preferable among the above optional components because it can further improve the coating performance of automobile members. Further, as the light stabilizer, high weather resistance can be imparted by adding at least one selected from a benzoate compound and a hindered amine compound having a molecular weight of 500 or more. When the light stabilizer is compounded, the compounding amount thereof is usually 0.01 to 100 parts by weight of the whole composition.
2.5 parts by weight.

[II] Manufacture of Molded Article for Automobile Parts (1) Manufacture of Resin Composition The coated automotive member of the present invention has the above-mentioned components (a) to
(g) each component, the resin composition obtained by blending in the above-mentioned ratio, using a single kneader such as a single-screw extruder, twin-screw extruder, Banbury mixer, roll, Brabender plastograph, kneader It can be manufactured by kneading, granulating and molding. Usually, it is necessary to select a kneading and granulating method that improves the dispersion of each component, and usually, the kneading and granulating is performed using a twin-screw extruder. At this time, the above component (a)
Each of the components (a) to (g) may be kneaded at the same time, or each component may be divided in order to improve the performance.
It is also possible to knead a part or all of the component (e), and then divide or simultaneously mix the remaining components to carry out kneading and granulation. The kneading is generally performed at a temperature of 190 to 250 ° C., preferably 200 to 240 ° C., and generally 0.1 to 3
It is done for about a minute.

(2) Molding By using the resin composition thus obtained and molding by various molding methods, an automobile member used in the present invention can be obtained. Molding can be performed by a usual method. That is, any molding method such as injection molding, injection compression molding, compression molding, extrusion molding (sheet molding, blow molding) may be used, but among these molding methods, injection molding, injection compression molding from the viewpoint of manifesting effects. It is preferable to perform (press injection). The molded article for automobile parts molded by the above-mentioned method has a flexural modulus of 7,000 kg / cm ² or more, preferably 7,500 to 30,000 kg / cm ² , and particularly preferably 8,000 to 25, is of 000kg / cm ^2, the flexural modulus of the molded product is in the case of less than the above range is limited in scope as the automobile parts. In order to set the flexural modulus of the molded body to be in the range or more, it is generally obtained by restricting the blending of the flexible elastomer component or controlling the blending of the filler.

(3) Surface condition of molded article for automobile parts The surface oxygen atom concentration (O / C: atomic ratio) relative to carbon atoms on the surface of the molded article molded by the above method is 0.5% or more,
It is preferably 0.7% or more. Here, the surface oxygen atom concentration is determined by X-ray photoelectron spectroscopy (XPS / ESC).
Based on A), for example, ESCA 100 manufactured by Shimadzu Corporation
0 X-ray photoelectron spectroscopic device was used as an X-ray source
It is determined by performing elemental analysis on the material surface using. The oxygen atom concentration at this time means the abundance ratio (O / C) of oxygen (O) atoms and carbon (C) atoms, and the sensitivity coefficient of C _1s is 1.00 and the sensitivity coefficient of O _1s is 2.85. Data is calculated by using the ESPA 1000 data processing system for surface analysis. Oxygen atom concentration (O
When / C: atomic ratio) is less than the above range, the coatability is insufficient. In order to obtain the surface oxygen atom concentration (O / C: atomic ratio) or more, the properties and composition of the components (b), (c) and (d), and in some cases, the component (f) may be used. It is obtained by controlling the amount and the like.

[III] Coating The coated automotive member of the present invention can be obtained by directly coating the surface of the molded body with a coating material to form a coating film directly on the surface of the molded body. As a coating method for directly forming a coating film on the surface of the molded body, a conventional coating process can be adopted, which is a process excluding a surface modification process such as TCE degreasing treatment, primer coating, and plasma treatment. That is, directly to an automobile member molded with the resin composition,
It is to apply paint. As means for applying paint,
Although there are spraying, brush coating, roller coating, and the like, any method can be adopted in the method of the present invention. As the paint that can be used in the method of the present invention, generally widely used paints, for example, acrylic paints, epoxy paints, polyester paints,
Examples thereof include urethane-based paints, alkyd-based paints, melamine-based paints, and the like. Among these paints, acrylic paints, polyester paints, urethane paints, alkyd paints, and melamine paints are preferably used.
The coated automotive parts of the present invention generally have 10 to 1 paint.
It is applied in a thickness of 00 μm, preferably 15 to 70 μm, and the coating film usually has a remaining number of 100 in a cross-cut adhesion test.
Sheets, 400 g / cm or more, especially 700 to 2,000 g /
Since it is firmly adhered with a peel strength of cm, it has sufficient coating performance as an automobile member such as a fender, a door panel, a bumper, a spoiler, a mat guard, a side molding, a wheel cap and an instrument panel.

The thus obtained coated automobile molded article of the present invention has a practically sufficient coating strength only by directly applying a coating, unlike a conventional molded article molded from a polypropylene resin. Its flexural modulus is 7,000k
g / cm ² or more, preferably 7,500 to 30,000
kg / cm ² , particularly preferably 8,000 to 25,000
It is of 0 kg / cm ^2, and beautiful appearance, and has a practical sufficient impact strength.

[0026]

EXAMPLES The present invention will be described in more detail with reference to experimental examples. The coating and evaluation methods performed here are as follows. (1) painting paint Examples 1-7 and Comparative Examples 1 to 3 using an acrylic melamine paints, Example 8 was conducted painted with polyester urethane paint. Painting method Each paint is blended individually, using an air spray gun,
Spray coating was performed so that the coating film thickness was about 25 μm and 60 μm. Baking process

(2) Evaluation method (a) Evaluation of paint adhesion Cross-cut test A parallel line of 11 vertical and horizontal lines was drawn at 2 mm intervals on the surface of a test piece coated with a thickness of 25 μm using a single-edged razor. Make 100 squares. Cellophane pressure-sensitive adhesive tape (JIS-Z1522) was sufficiently pressure-bonded on top of it, and was peeled off at a stretch while maintaining it at about 30 degrees with the coating surface, and the state of the part surrounded by the cross-cut was observed and it was not peeled off. The number of crosses was recorded. In addition, in the hot water resistance test, 4
After immersing in warm water of 0 ° C. for 240 hours, the same evaluation was performed. The surface of the test piece coated with a peel strength of 60 μm was linearly cut with a single-edged razor in a width of 1 cm, and the band-shaped portion of the coating film was pulled by a tensile tester at a speed of 20 mm / min. At that time, the load at the time of peeling and pulling was read.

(B) Mechanical strength evaluation Flexural modulus was measured according to JIS K-7203. The measurement temperature is 23 ° C. Izod impact strength (with cutting notch) Measured according to JIS K-7110 (cutting notch). The measurement temperature is -30 ° C.

(C) Measurement of surface oxygen concentration It is determined by X-ray photoelectron spectroscopy (XPS / ESCA). : Obtained by performing elemental analysis of the material surface using an ESCA 1000 X-ray photoelectron spectrometer manufactured by Shimadzu Corporation using MgKα as an X-ray source. The oxygen atom concentration means the abundance ratio (O / C) of oxygen (O) atoms and carbon (C) atoms on the material surface, and the sensitivity coefficient of C _1s is 1.00,
The sensitivity coefficient of O _1s is set to 2.85 and data is calculated by using the surface analysis data processing system ESPA 1000.

Examples 1-7 and Comparative Examples 1-3 Components (a), (b), (c), (d)
(e), component (f) and component (g) were mixed in the proportions shown in Table 1, and tetrakis [methylene-3- (3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate was added. ] 0.1 parts by weight of methane was mixed with 100 parts by weight of the total amount of the components (a) to (g), and these were sufficiently mixed with a high speed mixer (however, (e) of the filler component- The whisker part of 2 was excluded and the twin-screw extruder was used to feed from the middle). Then, after kneading and granulating under a temperature condition of 215 ° C. using a twin-screw extruder manufactured by Kobe Steel, (however, the whisker portion of the filler component (e) −2 is from the latter half of the extruder). The pellets thus obtained were fed to a screw in-line injection molding machine, and a test piece for measuring physical properties and a sheet for evaluating coatability (120 mm × 120) were supplied.
mm × 3 mmt) was molded at a temperature of 210 ° C. and evaluated. The molding cycle in this case is 45 seconds and 5 in total, respectively.
It was 0 seconds. The evaluation results are shown in Table 1. Component (a) Propylene / ethylene block copolymer containing 8% by weight of room temperature xylene-soluble component having ethylene content of 35% by weight, total ethylene content of 3% by weight, and MFR of 30 g / 10 min.

Component (b) b-1: Mooney viscosity ML _{1 + 4} (100 ° C.) of 25, ethylene / propylene copolymer rubber having a propylene content of 26% by weight b-2: Mooney viscosity ML _{1 + 4} (100 ° C.) 88, the ethylene / propylene / ethylidene norbornene terpolymer rubber having a propylene content of 28% by weight b-3: styrene content of 20% by weight, MFR (230 ° C.,
2.16 kg) 20 g / 10 min styrene / ethylene /
Butylene / styrene block copolymer

Component (c) c-1: Mooney viscosity ML _{1 + 4} (100 ° C.) of 5 or less (not measurable), MFR 45 g / 10 minutes, propylene content 25% by weight ethylene-propylene copolymer rubber c-2: Mooney viscosity ML _{1 + 4} (100 ° C) is 5 or less (not measurable), MFR 70g / 10 minutes, propylene content 23% by weight ethylene-propylene copolymer rubber

Component (d) The molecular weight produced from butadiene as the main raw material is about 2,9.
Produced by hydrogenating a diene polymer having a hydroxyl value of about 00 and a hydroxyl value of about 84, an iodine value of 1.0 (g / 100g) and a hydroxyl value of 8
Hydrogenated product of 3.7 (KOHmg / g) diene polymer

Component (e) e-1: Specific surface area is 39,800 cm ² / g, substantially the entire length is 10 μm or less, and the average particle size is 1.8.
Talc with an average aspect ratio of 6 in μm e-2: Aluminum borate whiskers with an average diameter of 0.6 μm and an average aspect ratio of 35

Component (f) Acrylic acid content is 15% by weight and MFR (190 ° C.,
2.16 kg) is 7 g / 10 min ethylene-acrylic acid copolymer

Component (g) Phosphoric acid di (2-ethylhexyl) ester and phosphoric acid di (2-ethylhexyl) ester
1: 1 mixture of ethylhexyl) ester

[0037]

[Table 1]

As shown in Table 1, the resin compositions having the compositions shown in Examples 1 to 7 have practically sufficient coating strength and mechanical strength, even though the moldings were directly coated with the coating material. Had strength. On the other hand, those shown in Comparative Examples 1 to 3 are
All of them had insufficient paintability or mechanical strength.

Example 8 The same resin composition as in Example 1 was used, and the polyester urethane-based paint was used for coating without any pre-coating treatment, and the evaluation was performed. The number of grids attached is 10
The peel strength was 0/100 and the peel strength was 1,020 g / cm.

[0040]

EFFECT OF THE INVENTION The resin composition molded article of the present invention is different from the resin composition molded article molded by the conventional polypropylene resin because the propylene resin composition blended with a specific composition is used. It has a practically sufficient coating strength by simply applying the paint directly, and also has a practically sufficient mechanical strength.Fenders, door panels, bumpers, spoilers, mat guards, side moldings, wheel caps, instrument panels, etc. It is excellent as an automobile member, and can simplify the coating process, improve the working environment, and reduce the cost.

Claims (1)

[Claims] 1. The following components (a), (b), (c), (d) and
(e), as the case may be, a resin composition consisting of each of the components (f) or (g) or both of them as an essential component is used as a raw material, and X-ray photoelectron spectroscopy (XPS-ESC) is used.
When the concentration of oxygen atoms to carbon atoms on the surface of the molded body measured by A) is 0.5% or more, the flexural modulus is 7,000.
A coated automotive member characterized in that a coating film is directly formed on the surface of a molded article for automotive parts which satisfies the condition of being kg / cm ² or more. Component (a): Contains 4 to 30% by weight of room temperature xylene-soluble matter having an ethylene content of 20 to 70% by weight, the MFR of the whole copolymer is 1 to 200 g / 10 minutes, and the ethylene content is Propylene / ethylene block copolymer of 3 to 21% by weight 40 to 80% by weight Component (b): At least one elastomer selected from ethylene elastomer and styrene elastomer 10 to 50% by weight Component (c) : Mooney viscosity ML _{1 + 4} (100 ° C.) is 5 or less, MFR (230 ° C., 2.16 kg) is 30 g / 10 min or more, and propylene content is 20 to 35% by weight of ethylene / propylene copolymer rubber 1 to 15 Weight% Component (d): Diene polymer having a hydroxyl group at the end or hydrogenated product thereof 0.01 to 10% by weight Component (e): Talc having an average particle size of 5 μm or less, or an average particle size of 2 μm or less Aluminum borate whiskers having an average aspect ratio of 5 or more, potassium titanate whiskers, magnesium sulfate whiskers (magnesium oxysulfate whiskers: MgSO4 · 5Mg (OH) 2 · 3H2O), titanium oxide whiskers and calcium carbonate whiskers. At least one filler selected from whiskers 3 to 40% by weight Component (f): Ethylene / unsaturated carboxylic acid copolymer 0 to 25% by weight Component (g): Phosphorus oxyacid compound 0 to 10% by weight